Tyrosinemia type 1 should be suspected in infants with severe coagulopathy even in the absence of other signs of liver failure.

Tyrosinemia type l is an inherited metabolic disorder attributable to deficiency of fumarylacetoacetate hydrolase, a terminal enzyme in the degradation pathway of tyrosine. Affected individuals may present with any of a number of signs and symptoms, including failure to thrive, fever, vomiting, diarrhea, hepatomegaly, ascites, jaundice, renal Fanconi syndrome, or conditions such as rickets and hepatocellular carcinoma.1 If untreated, the patient may die of acute liver failure before the second year of life, or from chronic liver failure or hepatocellular carcinoma before the end of the second decade of life.2 Although overt liver failure with coagulopathy may be part of the presentation of tyrosinemia, a significant coagulopathy in the absence of overt signs of liver disease has not been emphasized as a clue to the diagnosis of this condition. We report two tyrosinemic infants who presented with severe coagulopathies and no other signs of liver failure to stress this diagnostic point.